冲压模具激光表面强化的搭接工艺研究  

Study on overlapping process in laser transformation hardening of stamping die

作　　者：王恒海[1] 虞钢[1] 党刚[1] 何秀丽[1] 

机构地区：[1]中国科学院力学研究所先进制造工艺力学重点实验室,北京100190

出　　处：《材料热处理学报》2008年第6期168-172,共5页Transactions of Materials and Heat Treatment

摘　　要：针对激光相变强化搭接带存在的回火软化等问题,对激光强化的球墨铸铁材料QT700-2搭接区的显微硬度、表面粗糙度、物相变化等进行了测试,并分析了强化机理。结果表明:选用合理的搭接率等工艺参数,球墨铸铁激光搭接强化后的硬度可达到50HRC以上,调节搭接宽度可以避免搭接区的回火软化问题。多道搭接强化后表层的马氏体组织呈区域性交错分布,材料表面形成非均匀、多尺度强化结构,强化后的表面具有良好的耐磨性和耐疲劳性。通过上述结果,对材料激光搭接强化的工艺参数进行了合理的优化。Microhardness, surface roughness and phase transformation of overlapping zone in muhi-track laser hardening on a ductile cast iron QT700-2 were tested. The experimental results show that with proper processing parameters, the microhardness of treated layer can be higher than 50HRC. The temper softening in overlapping zone can be prevented by changing the overlapping ratio. The interlaced distribution of martensite and non-uniform, multi-scale structure in hardened zone after multi-track laser hardening led to a good wear and fatigue resistance of surface. Processing parameters of laser hardening on ductile cast iron were optimized.

关 键 词：脉冲激光相变强化 搭接工艺 球墨铸铁QT700-2 强化带 

分 类 号：TG156.99[金属学及工艺—热处理] TN249[金属学及工艺—金属学]